Page 261 - DCAP602_NETWORK_OPERATING_SYSTEMS_I

Unit 13: FTP Server

is the ‘compress’ program, indicated by a .Z suffix on the file notes
name. Also you will find Arc, Zoo, Arj, Lzh, gzipped or Zip files,

which are combined archival and compression formats (there are
other archival formats as well - talk to the systems staff if
you encounter them and don’t know how to deal with them).
For .zip files use zip and unzip (or pkzip/pkunzip), for .gz files
use gzip and for .Z files use compress, which are available for all
Operating Systems.
Archival and compression utilities are very handy, but can make

it very difficult to ‘get’ a file and use it:
when you’re on a DOS or VMS system for example you can’t type:

get filename.tar.Z

You have to type:

get filename.tar.Z filename.tz

or something like that and then remember what you have to do to
unpack the file, namely first running your version of ‘compress’
on it and then your version of ‘tar’.
Remember this when you can’t seem to transfer a file.

An interesting feature of most ftp servers in use today, is the
ability to compress and decompress ‘on the fly’. This means that
when you want to ‘get’ a .Z file, but you don’t have compress
handy, you can type: get filename.Z filename
The server will then decompress the file and leave you with a plain,

uncompressed file. Most servers support on-line decompression of
.Z, .gz and .tar files and even ‘get’ting an entire directory with
‘get directoryname directoryname.tar’. Note that this can take up
a huge amount of space and maybe take ages. Make sure you know what
you are doing when trying this.

These are the most common file types (there are zillions more):

SUFFIX FTP TYPE
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